The GGCA's newsletter "Waidmannsheil!"  The latest  issue #41 Fall 2009 has 3 articles on SS rifles. one of the articles was on "200 years of Swiss sharpshooter/military/schuetzen rifles" part 3. in this article the author is asking for help with a percussion Schuetzen with a "Plumb Bob" rear sight mounted on the barrel. An excellent photo (#7) is included in the article. I cannot figure out its function either. Another article Part 2 of 3 is titled "A Cold Case Reopened; Who Designed and Made Germany's "Best" Falling Block Action?
The third article is a report about the "Utah Schuetzen Society Annual Zimmerstutzen Matches"
I am going to have to try and find the previous articles of the two articles or order back issues, as they look pretty interesting.